The best sight I have seen is being on Mt. Fuji!!
I and several friend went up at night, in order to see he sunrise(but i got altitude sickness, and slept for 2 hours, missing the sunrise).
But while coming down, the air was so crisp and clear, and all you could see was lush green all around the mountain, was very beautiful(and unfortunately, I didn't know I had my camera in my side pocket, I had thought my friend had it! doh!).